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APPARATUSTOR DRYING TEA, HOPS, SLIOED FRUITS, &c. No. 416,157. PatentedDec. 3, 1889.

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APPARATUS FOR DRYING TEA, 1103s, SLIGBD FRUITS, &c. No. 416,157.Patented Dec. 3, 1889..

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APPARATUS FOR DRYING TEA, HOPS, SLIOBD FRUITS, 6w No. 416,157. PatentedDec. 3, 18 89 INVENTOR: WITESSES: M .1 1

(No Model.) '6 Sheets-Sheet 4.

S. G. DAVIDSON.

g APPARATUS FOR DRYING TEA, HOPS, SLIGBD'PRUITS, &c..

No. 416,157. Patented Dec. 3, 1889.

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(No Model.) 6 Sheets-Sheet 5. I S. G. DAVIDSON.

APPARATUS FOR DRYING TEA, HOPS, SLIGED FRUITS, am. No. 416,157. PatentedDec. 3, 1889'.

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(No Model.) 6 sheets sheet 6. s. 0. DAVIDSON.

APPARATUS P011 DRYING TE HOPS, SLIOED FRUITS, 8:0. No. 416,157. PatentedDec. 3, 1-889 N. PETERS. 'Pmw-Lm n m. Walhingtnn, D. c.

UNITED STATES PATENT OFFICE.

SAMUEL OLELAND DAVIDSON, OF BELFAST, IRELAND.

APPARATUS FOR DRYING TEA, HOPS, SLICED FRUITS, 84.0.

SPECIFICATION forming part of Letters Patent No. 416,157, dated December3, 1889.

Application filed February 14, 1889. Serial No. 299,893. (No model.)Patented in England September 5, 1888, No. 12,844.

To aZZ whom it may concern.-

Be it known that I, SAMUEL CLELAND DA- VIDSON, of Belfast, Ireland, asubject of the Queen of Great Britain and Ireland, have invented certainnew and useful Improvements in Apparatus for Drying Tea, Coffee, Cocoa,

Cinchona, Hops, Sliced Fruits, Seeds, Meal, or

. from bottom to top of the column without the ferred form.

material being whirled by the strength of the current into heaps on thetrays while in the drying-chamber, or blown away off them by it when thetrays are being put into or taken out of the apparatus.

.The present improvements consist in the construction of the apparatusfor carrying out this object.

In the accompanying drawings, Figure 1 is a front elevation; Fig. 2,avertical section on line 1 1 of Fig. 1; Fig. 3, a horizontal section online 2 2 of Fig. 1, the fan box or case not being in section; and Fig.4, a vertical section on line 3 3 of Fig. 3 of an apparatus c011-structed according to my invention in its pre- In this modification anexhaustfan is employed to produce the current of air down through thetrays. The device for temporarily checking or diminishing the draft whenany of the trays are being inserted or withdrawn consists of athrottle-valve, and is fitted to the outlet or exhaust port from thedrying-chamber, and a lift arrangement for moving up all the trayssimultaneously and pawls for retaining them when moved up are provided.Fig. 5 is a vertical section showing a modification in which agridiron-valve is employed in place of the throttle-valve. Fig. 6 isa'sect-ion taken at right angles to the section of Fig. 5.

Referring first to Figs. 1 to 4, A is the drying-chamber.

B is the inlet-port for the heated or desiccated air. p O is the airoutlet or exhaust. This, as shown, is made of a sheet-iron chamberprojecting from the fan-opening in the side of the chamberA into thespace below the trays, and has a rectangular opening or port C intowhich a throttle-valve D is fitted.

T T are the sieves or perforated trays. Each of these is fitted withcarriers [7 U for supporting the tray next above.

P is a doorway or tray-port opposite the lowest tray for the insertionof the trays, and R is a similar doorway or tray-port opposite thetopmost tray for the withdrawal of the trays. Each of these tray-portsis fitted with a door for closing same, (marked, respectively, Q and RLL are vertical bars or lifters for moving up the pile of trayssimultaneously. These bars or lifters are operated by means of thehand-lever G,which is centered on the shaft or spindle II, on whichspindle are mounted beam-levers J 3'. These beam-levers at one end actdirectly upon the bars or lifters L L at the back of the apparatus, andsimultaneously, through the intermediation of other beam-levers K K,upon the bars or lifters L L at the front of the apparatus.

O O are guides for the bars L L.

M M are pawls or catches, which support the lowest tray T when this hasbeen pushed up by the bars L L. These pawls are moved aside by the trayas it is being pushed up; but when the tray has passed them theyimmediately drop in by reason of their own weight and support it.Instead of the weight of these pawls being depended upon to insure theirdropping into position, they may be fitted with springs M as shown invertical and horizontal sections, respectively, in Figs. 5 and 6.

G is a segmental catch-bar for holding the lever G in the requiredpositions.

N N are angleiron rails or slides for the bottom tray when firstinserted.

N N are angle'iron stops to prevent the trays being lifted past theupper tray-port R.

F is a lever fitted on the shaft H and connected by a link F to thethrottle-valve D.

' closing the valve D.

Thus as the shaft H turns when operated on by the lever G, so as to openthe lower trayport door Q to let in a fresh tray and lower thelifting-bars L L to receive this tray, the valve D is caused to closeagainst the top and bottom portions O of the exhaustchamber 0. The topportion 0 serves as a chute to guide to the middle of the dryingchamberany material that may fall through the trays. The spindle of thevalve 1) turns in bearings C C in the sides of the exhaustchamber.

Q is the door of the lower tray-port P. It is attached to thelifting-bars L L and moves therewith.

S is the exhaust-fan.

V is a door to allow of the removal, when necessary, of any of theintermediate trays.

WV is a door for giving access to the base of the drying-chamber.

The operation of the apparatus is as follows: When a tray has to beinserted, the lever G is moved so as, through the in termediation of thebeams J J and K K, to lower the bars L L, the same movement having theeffect of opening the door Q, and, through the intermediation ofthe'lever F and link F of The tray is then inserted through thetray-port P. The lever G is then returned to its first position, wherebythe bars L L are raised, so as to lift the tray (with all others thatare above it) to close the door Q and to open the valve D. The traypasses the pawls M, and these then drop under the tray, so as to supportit. The same operation is repeated at the insertion of every followingtray, it being of course understood that if the chamber contains itsfull complement of trays the topmost one must be withdrawn through thetray-port R before another is inserted through tli'e tray-port P.

The air-current down through the trays may be produced by pressure-blastwith fans or other suitable blowing apparatus, and on being driven intothe air-space above the top tray it will of course find its way downthrough the trays to the outlet-port; but the current is preferablyproduced down through the trays by exhausting the air from below thetrays by means of an exhaust-fan S, as shown, or by a suitable air-pump;or a powerful chimney-draft can be connected to the outlet-port. The airmay be heated by any suitable air-heating appliancessueh as anair-heating stove or steam-pipes or pipes heated directly by fire; orcool desiccated air may be used, and its desiccation may be effected byan y suitable desiccatin g operation while they are in proper positionwithin the chamber, as the stronger the current the more firmly is thematerial held in its place on the trays, Whereas were the current upwardthrough the trays it would lift the material or whirl it about intoheaps upon them; but while the trays are being inserted or withdrawnthere would be, when means are not taken to prevent it, such a strongindraft through the bottom tray-port when the aircurrent is beingproduced by an exhaust from below the bottom tray or outdraft throughthe top tray-port, if it is produced by a pressure-blast delivered abovethe top tray, that the rush of air would be so strong that the materialon the trays would be blown oif them. valve or appliance, ashereinbefore described, for temporarily checking or diminishing thedraft or current while the trays are being inserted or withdrawn fromtheapparatus.

Referring now to the modification shown in Figs. 5 and 6, D is thegridiron-valve employed in lieu of the throttle-valve in Figs. 1 to 4.This valve is operated from one of the lifting-bars L through theintermediation of the rod F and bell-crank F Vhat I claim, and desire tosecure by Letters Patent, is-

1. In an apparatus for drying substances by means of a strong down draftor current of heated air or cool desiccated air, the combination of adrying-chamber, a column of perforated trays in said chamber, a trayinletrport at the bottom of said column, a tray outlet-port at top ofsaid column, doors to said inlet and outlet ports, an inlet for thecurrent of air at the upper end and an air outlet or exhaust at thelower end of said chamber, a valve or damper fitted to said airoutletfor temporarily cutting off or diminishing the air current or draft whenany of the trays are being inserted or withdrawn, and a connection,substantially as described, between the valve or damper and the door ofthe tray inlet-port,whereby when said valve or damper is open the saiddoor is shut, and vice Versa, substantially as and for the purpose setforth.

2. I11 an apparatus for drying substances by means of a strong downdraft or current of heated air or cool desiccated air, the combinationof a. drying-chamber, a column of perforated trays in said chamber, atray inlet-port at the bottom of said column, a tray outlet-port at thetop of said column, doors to said inlet and outlet ports, an inlet forthe current of air at the upper end and an outlet or exhaust at thelower end of said chamber, a valve or damper fitted to the saidair-outlet for temporarily cutting off or diminishing the air current ordraft when any of the trays are being inserted or withdrawn, bars orlifters for raising all the trays simultaneously, pawls or catches forsupporting the trays when raised, and-an appliance, substantially asdescribed, for simultaneously operating the valve or damper, the door ofthe tray in let-port, and the bars or lifters, the valve or It is forthis reason that I employ a IIO damper being open when the door of thetray inlet-port is shut and the bars or lifters are raised, and viceversa, substantially as and for the purpose set forth.

3. In an apparatus for drying substances by means of a strong down draftor current of heated air or cool desiccated air, the combination, withthe drying-chamber A, movable sieves or perforated trays T within saidchamber, air-inlet B at the upper part of said chamber, exhaust-outlet Oat the lower part of said chamber, valve D, controlling said outlet, andfan S, of the bars or lifters L, for raising said trays, pawls orcatches M, for supporting said trays when raised, and the pivoted leverG, said lever being connected to said valve and to said bars or lifters,substantially as and for the purposes set forth.

4. In an apparatus for drying substances by means of a strong downdraftor current of heated air or cool desiccated air, the combination, withthe drying-chamber A, movable sieves or perforated trays T within saidchamber, air-inletB at the upper part of said chamber, exhaust-outlet Cat the lower part of said chamber, fan 8, bars or lifters L, for raisingsaid trays, pawls or catches M, for supporting said trays when raised,and pivoted lever G, for operating said valve and said bars or lifters,of the shaft H, carrying said lever, beam-levers J J and K K, connectingsaid shaft and said lifters L, lever F, and link F connecting said shaftand said valve D, substantially as and for the purpose set forth. 7

5. In an apparatus for drying substances by means of a strong down draftor current of heated air or cool desiccated air, the combination, wit-hthe drying-chamber A, movable sieves or perforated trays T within saidchamber, air-inlet B at the upper part of said chamber, exhaust-outlet Cat the lower part of said chamber, valve D, controlling said outlet,bars or lifters L, for lifting said trays, and pawls or catches M, forsupporting said trays, of an upper tray-port or doorway R in the upperpart of said chamber, lower trayport or doorway P in said chamber, and adoor Q to said port P, said door being attached to the front bars orlifters L, so as to move therewith and to close the port when said barsare lifted, substantially as and for the purpose set forth.

6. The combination, substantially as described, of the drying-chamber A,air-inlet B thereto, exhaust-outlet G therefrom, fan S, valve D,controlling said outlet, trays or sieves T within said chamber, trayinlet-port P, door Q of said inlet-port, tray outlet-port R, door Rthereof, bars or lifters L, for raising said trays and connected withsaid door Q, pawls or catches M, for holding said trays when raised,lever G, notched segmental bar G coacting with said lever, shaft H, towhich said lever is secured, beam-levers J and K, connecting said shaftII and lifters L, lever F, and link F connecting said shaft H and valveD, substantially as and for the purposes set forth.

In witness whereof I have hereunto signed my name in the presence of twosubscribing witnesses.

SAMUEL CLELAND DAVIDSON.

Witnesses:

WILLIAM JOHN DEVERS, THOMAS WILLIAMs PUGH.

